Chickenpox is a very common infectious disease that can affect people of all ages, but most often it affects children up to 10 years of age. The disease is not dangerous, but its course may be riskier in adults (more severe symptoms) and pregnant women (possible fetal damage). Right at the beginning of this short article I would like stress that this disease is completely different from the smallpox.
The cause of the chickenpox is the so-called varicella-zoster virus. This virus easily spreads in children collectives as a droplet infection. The ill children cough up the microorganisms and they are inhaled by others, thus causing rapidly spreading epidemic.
In contrast, the smallpox is caused by the variola virus, which also spreads by droplets. The disease used to be extremely dangerous with a high mortality. Today, thanks to the smallpox vaccination the variola virus has been worldwide exterminated. Well, probably not completely, as some strains of smallpox virus is still kept in military laboratories of the main world power as a potential biological weapon. In case of such situation, the result would be a terrible pandemic with hundreds of millions of deaths. And now let us go back to the chickenpox.
The symptoms occur in one to two weeks after the contraction of the disease. The disease starts as a skin rash with high fever. The rash is itchy with small papules that change into small blisters filled with clear fluid or pus. The rash is typically present on the face and the trunk. Less common affected areas include the upper and lower extremities, the head and mucous membranes in the mouth.
The disease has a complicated course in pregnant women as it can damage the fetal tissues. Fetuses before the 28th week of the pregnancy are especially endangered. Adults in general have a more severe course of the disease with a very high fever and a widespread rash that may heal by scars.
The varicella-zoster virus is not fully removed by the immune system. After the symptoms disappear, the viral particles remain hidden in the human body within the nerve ganglia, which are clusters of neurons located in the vicinity of the spine. Out of there, the virus may reactivate. However, such reactivation does not cause the chickenpox, but so-called shingles.
The diagnosis can be easily stated by a pediatrician or a skin doctor according to the clinical symptoms and positive epidemic history.
In childhood, the prevention is not strictly needed as the infection has an uncomplicated course. There are even organized the so-called “pox parties” where children are brought to a household with an ill child to contract the disease. However, vaccination is possible, which can prevent the individual from contracting the disease at all. Adults and especially pregnant women should strictly avoid the contact with any sick individual. A vaccine is available in many countries. Usually it is a voluntary vaccination that prevents both the chickenpox and occurrence of shingles later in the life.
The treatment is essentially symptomatic. The child should stay at home (bed rest) and the rash can be locally treated with liquid powder and antihistaminic drugs may be prescribed to quell the itching. Severe cases may be treated with antivirotics, but this is not a regular approach.